The importance of proper marking (labeling) of mammograms can not be overstated. To properly interpret a mammogram, the radiologist must be aware of the precise view under study, which is difficult due to the similarity in appearance of views such as medio-lateral oblique and craniocaudal views, and other diagnostic views of breast tissue. Thus, a clear, concise identification (mark) must exist on the X-ray film to resolve ambiguity.
Lead letters are the generally accepted method of marking or identifying the mammogram on X-ray film by preventing X-ray energy from exposing the film directly underneath the letters. When the film is developed, the letters will stand out as white against a dark background. The exact sequence of letters which identify the various mammographic views are specified by the American College of Radiology.
To assist the radiologist who is interpreting (reading) the mammographic film, the letters identifying the view should be located in a specific location on each film. This permits the radiologist to spend more time studying the breast tissue under consideration and to thus be more productive.
Marking systems currently in use either can not be reversed or they can not be readily identified when in position since their letters are obscured by the mounting means utilized. For example, with a normal X-ray exposure of the film the identification code for a medio-lateral oblique projection view will be read as "RMLO" when the film is viewed emulsion side DOWN on the view box. However, if the radiologist wants to examine the film with the emulsion side UP, the label code would read "OLMR", causing distraction and possibly misinterpretation. When the marker can be applied to the bucky in the reversed position, then an emulsion side UP would be "right reading" and the emulsion side DOWN would be "wrong reading." Most of the current marking systems can not be easily reversed to provide "right reading," and those that can be reversed, for example, those that are taped onto the bucky, can not be readily identified by the X-ray technologist as to the view and/or whether the letters are upside down or not, prior to the exposure of the film.
The systems of attaching markers using glue, tape, or suction cups are troublesome. These methods are deficient in that they do not permit consistent, repeatable location of the markers or easy identification of the view in question, and the markers are sometimes difficult to apply.